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Shahr-e Kord, Iran

Darvishsefat A.A.,University of Tehran | Abbasi M.,University of Shahre kord | Schaepman M.E.,University of Zurich
Journal of Agricultural Science and Technology | Year: 2011

Rice cultivated areas and yield information is indispensable for sustainable management and economic policy making for this strategic food crop. Introduction of high spectral and special resolution satellite data has enabled production of such information in a timely and accurate manner. Knowledge of the spectral reflectance of various land covers is a prerequisite for their identification and study. Evaluation of the spectral reflectance of plants using field spectroradiometry provides the possibility to identify and map different rice varieties especially while using hyperspectral remote sensing. This paper reports the results of the first attempt to evaluate spectral signatures of seven north Iranian rice varieties (Fajr, Hybrid, Khazar, Nemat, Neda, Shiroudi and Tarom plots) in the experimental station of the Iranian Rice Research Institute (main station in Amol, Mazanderan Province). Measurements were carried out using a field spectroradiometer in the range of 350-2,500 nm under natural light and environmental conditions. In order to eliminate erroneous data and also experimental errors in spectral reflectance curves, all curves were individually quality controlled. A set of important vegetation indices sensitive to canopy chlorophyll content, photosynthesis intensity, nitrogen and water content were employed to enhance probable differences in spectral reflectance among various rice varieties. Analysis of variance and Tukey's paired test were then used to compare rice varieties. Using Datt and PRI1 indices, significant differences (α= 0.01) were found among rice varieties reflectances in 19 out of 21 cases. This promises the possibility of accurate mapping of rice varieties cultivated areas based on hyperspectral remotely sensed data. Source

Hashemzadeh Segherloo I.,University of Shahre kord | Bernatchez L.,Laval University | Golzarianpour K.,Golestan University | Abdoli A.,Shahid Beheshti University | And 2 more authors.
Journal of Fish Biology | Year: 2012

The phylogenetic relationship between two sympatric morphotypes of the Iran cave barb Iranocypris typhlops, and Garra rufa, was investigated by sequencing the cytochrome c oxidase I (coI) region (788 bp) providing the first molecular evidence of their phylogeny. Consistent with their morphological differences, the mean genetic distance between the two forms of I. typhlops was significantly higher than generally reported for intraspecific divergence in freshwater fishes. They were phylogenetically closer to G. rufa than to any other species. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles. Source

Taghizadeh-Mehrjardi R.,University of Yazd | Akbarzadeh A.,University of Shahre kord
Archives of Agronomy and Soil Science | Year: 2014

Nine pedons and 30 surface samples were taken, described, and analyzed to investigate the effect of desertification on soil quality indices, mineralogical, and micromorphological properties of three regions (desert, semi-desert, non-desert) in central Iran. The results showed that moving from a non-desert to a desert area decreased soil quality indices such as organic matter (from 0.5% to 0.2 %) and microbial respiration (from 1.59 to 0.11 mgCO2 g-1 soil). By contrast, increases were recorded for bulk density (1.2 to 1.9 Mg m-3) and soil salinity (5 to 19 dS m-1). Soil in the non-desert area had a sandy texture that led to good drainage conditions, while soil in the desert area had a clayey texture that led to poor drainage conditions. The mineralogical assemblage of the soil was approximately the same for all the three areas, with illite and chlorite being the main minerals. Kaolinite and smectite were present in lower concentrations. The micromorphological evidence showed that the main microstructure of the non-desert region was granular, probably because of the higher organic matter content in this area. In the desert region, platy structure was abundant. Overall, a more thorough perception of the desertification process was gained by studying its impact on soil properties. © 2013 Taylor & Francis. Source

Abbasi M.,University of Shahre kord | Bakhtyari H.R.R.,Shiraz University
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2012

Tree crown size (CS) and stem number per hectare (SN) has become increasingly important for forest management and ecosystem monitoring. Tree crown size is also strongly related to other canopy structural parameters, such as diameter at breast height, tree height and biomass. For both issues, remote sensing data are attractive for their large-area and up-to-date mapping capacities. The QuickBird and ASTER imagery used in this study was acquired over Zagros Forests in southern Zagros region, Fars province of Iran on 1 August 2005 and 1 July 2005, respectively. For the forest site investigated in this study, we concentrated on stands of Quercus Persica which is the dominant species in Zagros region. This study was conducted to investigate the capabilities of ASTER-L1B data to estimate some of forest parameters at individual tree and stand level in dry area. The forest stand parameters are crown area, crown density, average crown area. Obtaining the accuracy of classification the ground truth map was prepared by tree crown delineation using the panchromatic band of QuickBird data. Individual tree crowns were automatically delineated by color segmentation of QuickBird imagery. Simple linear regression procedure was used to show the relationships between spectral variables and the individual trees and forest stand parameters. With decreasing the crown density the effects of background will increase. Our results indicated that crown size could be accurately extracted from panchromatic band of QuickBird images especially for open forest stands. This paper demonstrates that using high-resolution satellite imagery in the open forest offers a unique opportunity for deriving single tree attributes and allowing reliable ground truth map to estimate stand structure. ASTER data and its indices showed good capability to estimate crown area in this study. © 2012 ISPRS. Source

Ahanjideh N.,University of Shahre kord | Rezaeezadeh G.R.,University of Shahre kord | Safari S.,University of Shahre kord
Iranian Journal of Science and Technology, Transaction A: Science | Year: 2013

In this paper, it was shown that 2Dn(2), where n=2m+1 ≥ 5 and |π(2n-1+1)|=1, and 2Dn(3), where n=2m+1 ≥ 9 is not prime and |π(3n-1+1/2)|=1, are OD-characterizable. Source

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